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51.
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Airway hyperresponsiveness (AHR) is a characteristic feature of asthma, but is also frequently demonstrated by children and adults with chronic obstructive lung diseases. AHR is usually measured by bronchial challenges using direct or indirect stimuli. The aim of this study was to compare these two types of bronchial challenge in children with post-infectious bronchiolitis obliterans (BO). Methacholine and adenosine 5'-monophosphate (AMP) challenges were used as tools for the evaluation of AHR to direct and indirect stimuli, respectively, in children with post-infectious BO (n = 28). These results were compared with those of asthmatic (n = 30) and control children (n = 25). Altogether, twenty-two patients (78.6%) with post-infectious BO were hyperreactive to methacholine with a provocative concentration causing a 20% fall in forced expiratory volume in one second (PC20) of <16 mg x mL(-1), but only six (21.4%) were hyperreactive to AMP with a PC20 of <200 mg x mL(-1). All patients with asthma responded positively to methacholine, and most (28, 93.3%) also responded positively to AMP. The majority of controls were insensitive to both challenges. Airway hyperresponsiveness to methacholine is a frequent, but by no means universal, finding in children with post-infectious bronchiolitis obliterans, but is usually not accompanied by airway hyperresponsiveness to adenosine 5'-monophosphate. This finding suggests that airway hyperresponsiveness in patients with post-infectious bronchiolitis obliterans has characteristics that differ from those of asthmatic subjects.  相似文献   
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We describe the enhancement patterns of myoepithelioma in two patients with a soft palate mass. In the first case, helical CT revealed a faintly enhancing mass. Histologically, the tumor was composed of plasmacytoid cells in a background of rich myxoid stroma. Immunostaining for CD34 showed scanty blood vessels. In the second case, helical CT revealed an intensely enhancing mass. Histologically, the mass was a cellular tumor with fibrous stroma. Immunostaining for CD34 also showed frequent blood vessels.  相似文献   
55.
De novo renal cell carcinoma in a renal allograft is rare and has special implications in renal transplant recipients. We describe a patient with a renal allograft who developed a de novo renal cell carcinoma in the functioning renal allograft 258 months after transplantation. The patient underwent enucleation of the tumor because preoperative MRI showed it was well-encapsulated. A DNA banding study showed that the tumor originated from the donor. Indications for conservative renal surgery in renal cell carcinoma have been increasing. Accordingly, 1 option in the treatment of de novo renal cell carcinoma in a functioning renal allograft is enucleation as a method of nephron sparing surgery.  相似文献   
56.
本文通过将无环鸟苷(acyclovir,简称ACV)2’位羟基分别与月桂酰氯或棕榈酰氯进行酯化反应,制得亲脂性前体药物无环鸟苷月桂酸酯和无环鸟苷棕榈酸酯(分别简称为C12-ACV和C16-ACV),使脂质体包封率从ACV的29.9%提高到C12-ACV的95.6%和C16-ACV的97.1%;漏泄实验表明在4℃透析60h后,一半以上的ACV从脂质体中漏泄,而C12-ACV和C16-ACV的滞留率分别为70%和80%;体外抗疱疹病毒的试验中,在最低试验浓度0.044μmol/L时,ACV不显示抗病毒活性,而C16-ACV脂质体抑制细胞病变率达75%,说明前体药物通过与脂质体脂膜的结合增加了药物的进入细胞能力,从而提高了ACV的抗病毒能力。  相似文献   
57.
Rett's syndrome(RS) is a progressive neurodegenerative disorder characterized by exclusive occurrence in females, autistic behavior, dementia, gait ataxia, loss of purposeful use of the hands with stereotypic hand movement, and seizures. Initially RS was considered to be very rare; however, recent reports suggest that the prevalence is considerably higher and occurrence is world-wide. Because the pathophysiological process remains unknown, the diagnosis of RS is based mainly on its characteristic clinical features and course. We experienced two cases of RS which, to our knowledge, are the first reported in Korea. It is quite possible that many patients with RS not yet being diagnosed in Korea.  相似文献   
58.
Data from the National AIDS Behavioral Survey were used to examine the social distribution of extramarital sex and risk for human immunodeficiency virus (HIV) infection among married individuals in the United States. Of 1686 married respondents living across the United States, 2.2% reported extramarital sex; of 3827 married respondents living in 23 urban areas with large Hispanic or African-American populations, 2.5% reported having sexual partners outside marriage. The data indicate that the correlates of extramarital sex varied by race/ethnicity. Low levels of condom use were found among people reporting extramarital sex (8% to 19% consistent users).  相似文献   
59.
To further investigate a clinical impression that patients with early onset pauciarticular juvenile rheumatoid arthritis (EOPA-JRA) who carry HLA-DQw1 have more severe arthritis, we subtyped HLA-DQw1 in American midwestern patients with EOPA-JRA. The HLA-DQA1*0101 subtype was present in 10 of 19 patients who developed persistent polyarticular erosive disease compared with 18 of 92 healthy controls (chi 2 = 9.13, p = 0.003, RR = 4.6), and occurred more frequently in this polyarticular group than in patients without polyarticular erosive disease (chi 2 = 4.11, p = 0.040, RR = 3.0). The presence of HLA-DQA1*0101 was significantly lower in patients with chronic iridocyclitis than in patients without chronic iridocyclitis (chi 2 = 7.07, p = 0.008, RR = 0.21). In HLA-DQA1*0101 positive patients, DNA sequences of the beta-1 domain of the HLA-DQ alpha and HLA-DQ beta genes (HLA-DQA1*0101, HLA-DQB1*0501 and HLA-DQB1*0503) were identical to those in controls. In this midwestern EOPA-JRA population, HLA-DQA1*0101 or genes in linkage disequilibrium with it, are associated with a cohort of patients with EOPA-JRA with distinct clinical characteristics.  相似文献   
60.
Objects We designed several distraction devices and applied these instruments in 14 patients with varying types of craniosynostosis. The aim of this report is to clarify the advantages and disadvantages of these surgical methods and to discuss current concepts for the surgical strategy in the treatment of craniosynostosis. Methods From January 2000 to July 2005, 28 patients with craniosynostosis were retrospectively analyzed. Surgical treatment was performed on 14 patients using the distraction method with internal distraction devices that we designed, in which 5 patients had plagiocephaly, 3 brachycephaly, and 6 scaphocephaly. All patients underwent preoperative and postoperative evaluations, which included the patient’s neurological state, and three-dimensional CT. Results With distraction devices, the time required for the surgery could be shortened almost 3 1/3 h; the bleeding during the surgery was decreased with reduced requirement of more than 200 ml of blood transfusion as compared with remodeling surgery. Postoperatively achieved distraction distances varied from 30.0 to 47.5 mm (mean, 42.99 mm). The average increased volume percent of cranium in distraction surgery group was 20.9% (range, −11.5 to 58.9%) after full distraction. Conclusion With distraction surgery, satisfactory cranial volume expansion and aesthetically pleasing morphological states were achieved in all cases, and the efficacy was statistically significantly high as compared with remodeling method.  相似文献   
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